Hi Guys,
I'm keen to get started since I wanted to see a vintage AR forum
I'll go easy for starters since it's the first time I've emailed photos in to Brad for the forum.
1968 homebrew HF SSB transmitter/receiver (split VFO) 20/40/80 meters - VK4QT silent key.
This, among some other older gear was donated to my club after the original owner's passing, and in turn donated to me to get running although I'm not licensed to the level of transmitting into the air with a homebrew transmitter yet. Tho I'm asking if the freq is in use on the YouTube video, I was talking to myself. It didn't go out into the air.
This is probably among the first SSB homebrew in my area.
This one is just a bit of depressionary era show & tell.. hard to beat the charm of this.
No restoration other than new electrolytics needed, and I can receive off the air,
and verified transmit into dummy load while monitoring with a coupled modern receiver.
It only requires a little adjustment for carrier suppression (balanced modulator).
The schematic was provided, and dated Nov 1968 (transmitter), and Dec 1968 (receiver).
25 valves total, and four solid state diodes! The schematic sample of the PA section is just an idea of what it looks like.
Receiver test on YouTube:
https://www.youtube.com/watch?v=7sJWXOYXItU.
Transmitter test on YouTube:
https://www.youtube.com/watch?v=x1x-WJsGtvY.
The unit came with a GDO dated right there on the label May 1965 and works unmodified.
I found out later that this was a project day done at my club, and there are other identical units around, including an incomplete one still sitting at my club.
Grid Dip Oscillator test on YouTube:
https://www.youtube.com/watch?v=Ch_MHJSHnIA.
Later, the owner makes this replacement, but it's 40 meter only. It still has a valve power amplifier similar in style to the above unit.
Since this needed little work, I didn't learn much other than how someone can care about quality of construction using any old parts available, and how difficult the rig would be to use practically today!
When my licensing is up to advanced, I aim to lock the entire rig to freq digitally, and host a net with it.
Since this thread might be Google searchable, greetings to the current VK4QT, and respect for the former VK4QT's work.
Want to see more? Let me know, next up is complete restoration of a commercial transceiver
Cheers, Brek (VK4FAST) - VK4WIP Ipswich & District Radio Club.